Just a few things off the top of my head. Aside from the electronics, the open-bridge bulwark in front of the pilot house will have to be removed. The open bridge atop the pilot house will have to be reshaped (squared at the front and not extending to the front of the pilot house). The 40MM tubs beside the bridge structure will have to be elevated 1/2 level (they were lowered when 40MM replaced the 1.1's) and the quad 40MM tub on the quarterdeck removed and replaced with the smaller tub associated with the quad 1.1" mount. The searchlight tubs on the after stack will have to be repositioned, and some added by the forward stack. And a boat crane will need to be added in front of the after stack. The 20MM battery will also require adjusting. So, it all depends on what you consider to be "major surgery".